getting ps2 games to work

I've been reading all the problems everyone has had but i'm still unable to get my games to work. I use dvd decrypter and i think they burn ok but my ps2 is a version 4 with a no solder mod chip, but when i put the gameshark2 in i can't hit the x to make it work like the cdrom games do. what am i doing wrong????
when i started using the decrypter program it kept writing with a mds file instead of the iso file but i think i have that fixed now but it still doesn't work. please help thank you

yes i'm following the instructions to a tee on that page but i even tried nero and same results. i changed the book type on the dvd+r to dvd rom just like the games are but still nothing. starting to really irrate me.

well i changed the read setting from preforming the mds file because everytime i tried to write from the iso file it would automatically goto the mds file. regardless neither one works. i'm ready to give up, i bought a liteon burner and thought it would be easy but not for illiterate people like me. haha